Although the prevalence of obesity has rapidly increased in the low- and middle-income countries of the Middle East and North Africa (MENA) and Latin America and the Caribbean (LAC) regions, child undernutrition remains a public-health challenge. We examined region-specific sociodemographic determinants of this double burden of malnutrition, specifically, the co-occurrence of child stunting and overweight, using Demographic and Health Survey and Multiple Indicator Cluster Survey data (2003-2016) from 11 countries in the MENA (n = 118,585) and 13 countries in the LAC (n = 77,824) regions. We used multiple logistic regressions to model region-specific associations of maternal education and household wealth with child nutritional outcomes (6-59 months). The prevalence of stunting, overweight, and their co-occurrence was 24%, 10%, and 4.3% in children in the MENA region, respectively, and 19%, 5%, and 0.5% in children in the LAC region, respectively. In both regions, higher maternal education and household wealth were significantly associated with lower odds of stunting and higher odds of overweight. As compared with the poorest wealth quintiles, decreased odds of co-occurring stunting and overweight were observed among children from the second, third, and fourth wealth quintiles in the LAC region. In the MENA region, this association was only statistically significant for the second wealth quintile. In both regions, double burden was not statistically significantly associated with maternal education. The social patterning of co-occurring stunting and overweight in children varied across the two regions, indicating potential differences in the underlying aetiology of the double burden across regions and stages of the nutrition transition.